This is the second resubmission of a competitive renewal application for a post-doctoral hematology training program located at Children's Hospital Oakland Research Institute (CHORI). The program provides the opportunity for research training in hematology, immunology, genetics, hematopoietic stem cell biology, and transplantation with a focus on the application of these disciplines to the hemoglobinopathies. This application requests three trainees per year. The program will emphasize hands-on bench and clinical research work in the laboratory or clinical setting of an experienced, NIH-supported investigator. A committee will participate in the selection and evaluation of candidates, as well as in the laboratory assignment. Eligible trainees with PhD, MD/PhD or MD degrees will be recruited who have a strong background and interest in cell or molecular biology, genetics, biochemistry, transplantation biology or clinical research. At the beginning of the fellowship, each trainee will develop a research hypothesis and write a research proposal, which will be reviewed and approved by the directors and mentors. Trainees will participate in core curriculum activities, meet daily with mentors, and monthly with program directors. Trainees will complete didactic coursework in ethics and statistics, and have access to advance courses such as molecular biology and stem cell biology. Trainees will participate in weekly laboratory meetings, monthly journal clubs and weekly research seminars. Trainees will present their research at national scientific meetings, publish several manuscripts in peer-reviewed journals, and begin to seek extramural grant support during their second year. The research opportunities in areas funded by NIH at CHORI include: (1) clinical research in sickle cell anemia and thalassemia, (2) red cell membrane structure and function, (3) immunologic development and immune response to vaccines, (4) bioiron, molecular regulation of ferritin synthesis, and iron toxicity, (5) lipid mediated signal transduction in stem cell biology, (6) genetic polymorphisms contributing to disease severity, (7) cord blood stem cell biology, and (8) stem cell transplantation for patients with hemoglobinopathies. Upon completion, trainees will be prepared to continue to work in an academic setting in the field of hemoglobinopathies and become qualified, independent scientists